Recent developments for SPIE-IA, a new sandwich immunoassay format for very small molecules.

Abstract Recent publications describing new elegant approaches to assay small analytes using noncompetitive format were briefly reviewed. Among these methods, we have developed a new protocol, named SPIE-IA, which involves a cross-linking step achieved using chemical hombifunctional reagents, UV irradiation or free radicals. This new method proved to be useful to detect naturally occurring analyte/antibody complexes or to protect the analytes against degradation by peptidases. On the other hand, SPIE-IA could allow to study the adverse biological effects of UV and some aspects of free radical chemistry or to evaluate the antioxidant activity of molecules.